In those patients with diabetes, plasma levels of RBP4 were positively correlated with HbA1c (r = 0.347, P<0.0001), BMI (r = 0.163, P=0.001), Hs-CRP (r = 0.302, P<0.001), and duration of illness (r = 0.179, P<0.001). The gene discussed is RBP4; the disease is diabetes mellitus.